More and more sensors are used by consumer electronics, such as mobile phones, to save energy and improve human-machine interaction. For example, the latest mobile phone uses ten or more sensors. Therefore, engineers are eager to integrate sensors so as to save energy, space and cost.
The ambient light sensor is used to detect variation of an ambient light source so as to regulate brightness of a screen of the mobile phone. When the ambient light dims, the screen of the mobile phone also dims to prevent light of the screen from dazzling a user. When the ambient light brightens, backlight of the screen also brightens to enhance visibility of articles presented on the screen. Therefore, the ambient light sensor can save energy and increase a running time of the mobile phone. The proximity sensor is a non-contact object-detection sensor. In the mobile phones, the proximity sensor is used to disable a touch control function when the user is talking close to the phones. As soon as the user's head approaches an earpiece, the touch control function is automatically turned off lest the touch screen operates erroneously by touching the user's face. As both the ambient light sensor and the proximity sensor are optical systems, they are normally encapsulated in an identical package structure so as to share the space, materials, wiring and power source.